1. Technical Field
The present invention relates to a voltage converting circuit and a method thereof.
2. Background
Today, people increasingly depend on electronic products. To meet requirements of high speed, high performance, and features of lightness, slimness, shortness and smallness, various portable electronic products, such as notebook computers, cell phones, personal digital assistants (PDA) become more and more popular. Therefore, works can be handled at any time, anywhere, and are no longer limited to be handled in the office.
However, to cope with a demand of fast data processing, power consumptions of the aforementioned portable electronic devices powered by batteries are accordingly increased during the data processing. Namely, since a higher data processing speed results in higher power consumption, to effectively maintain a battery operation time is an important issue. Here, based on dynamic voltage supplying and load current scaling, an effective method for maintaining the battery operation time can be provided for active and standby power management.
Therefore, when the system is converted from a deep sleep mode to an active mode, a direct current (DC)-DC voltage converter thereof must be able to quickly supply power and switch a load current, and vice versa. Therefore, in an electronic device system, utilization of a high efficiency DC-DC voltage converter having a fast dynamic response for reference tracking and load transient is necessary. For example, in the electronic device system, a V2 control buck converter is used to provide the required voltages, so as to satisfy the aforementioned demand.
However, in the conventional V2 control buck converter, a load capacitor of a large equivalent series resistance (ESR) is required, so as to satisfy the above demand, which may result in a higher ripple of an output voltage thereof.